Tiny organisms living in the world's oceans could be used as an important indicator of climate change, according to new findings by an international team including a Norfolk scientist.

A study of a type of phytoplankton, a microscopic plant which lives in the ocean, called Micromonas, which had been previously overlooked, has been carried out using DNA techniques.

Dr Thomas Mock, from the University of East Anglia (UEA), who was among the team, discovered it thrived in oceans ranging from tropical to polar and in conditions that are predicted outcomes of climate change.

Co-author Dr Mock said: “This research shows that we need to look very carefully in the oceans because things that have been previously overlooked, such as the Micromonas species, may have a significant impact in the future ocean.

“If Micromonas and other tiny phytoplankton species dominate the future ocean, it might also have a significant impact on the entire marine food web because the food source for all other organisms will change.”

The study, published this week in the journal Science, shows that while other larger phytoplankton species such as Diatoms may not grow well under these conditions, the tiny Micromonas species - which is a fifth of the size of a human blood cell - can thrive under low concentrations of nutrients and is very well adapted to lower nutrient conditions, and therefore may become more dominant.

Although the existence of Micromonas was first reported in the 1950s, until now little has been known about it.

Scientists disregarded it because of its size and lower abundance under past and current conditions of the oceans.